The glycemic response to food (glycemic index) has been utilized in diabetic diets in the past, but this can be altered by other foods consumed during a meal. The investigators will examine the inter and intra- individual variability of the glycemic index of mixed meals (GIMM) in both diabetic and non-diabetic individuals. These results will allow diabetics to improve glycemic control by arranging daily menus using standard meals with established glycemic responses.